1) Two-thirds of Montreal boroughs reported no new #COVID cases on Tuesday, including former hot spots. Yet Quebec’s chief public health officer expressed concern people are taking things for granted. In this thread, I will try to explain the risks of this carefree approach.

2) “I must confess, I’m worried,” Dr. @ArrudaHoracio told Radio-Canada on Tuesday, noting that many people are not wearing face coverings in public. He warned that this could lead to a second wave or a resurgence in cases even during this first wave in the #pandemic.

3) It’s hard not to see why Dr. Arruda is concerned, given the experience in Florida, South Carolina and Arizona — U.S. states that all reopened in full a month ago. Those three states are observing not only surges in cases but increases in #COVID hospitalizations, too.

4) Although Quebec started loosening confinement measures five weeks ago, Montreal’s reopening began in earnest only on Monday when restaurants threw open their doors. Based on the U.S. experience, we'll probably have to wait a month to know if Montreal has succeeded or failed.

5) In the meantime, the city declared 17 #COVID cases Tuesday, the second lowest number in more than three months, as the orange line in the chart below indicates. But this comes amid a big drop in #COVID19 tests on Sunday.

6) Still, for at least two days in a row, none of Montreal’s long-term care centres and seniors’ facilities reported any new #COVID infections. And across Quebec, hospitalizations from the #pandemic illness continued to decline. (See below.)

7) At the neighborhood level, Mercier–Hochelaga-Maisonneuve and Rivière-des-Prairies–Pointe-aux-Trembles — boroughs which were once hotbeds of #COVID transmission — did not post any new cases on Tuesday. But again, authorities are testing fewer people.

8) Meanwhile, the metropolis posted two #COVID deaths, down from 31 only four days earlier, as the dark blue line in the chart shows. On Tuesday, Quebec added a fatality retroactively to Monday and that death is likely to have occurred in Montreal.

9) So the progress is undeniable. But Dr. Arruda is still worried. Instead of simply expressing concern, why doesn’t he recommend mandatory face coverings for public transit, as will soon be the case in Toronto? Why doesn’t he expand testing for asymptomatics as Alberta has done?

10) If and when there’s a resurgence, it’ll likely happen quickly. But unlike in March when the city’s emergency rooms were only half full, the chart below shows ER overcrowding is back in full force, hardly an ideal situation in anticipation of a second wave. End of thread.